RE: [PATCH 1/3] KVM: nVMX: Fix virtual interrupt delivery injection

Zhang, Yang Z
2014-07-17T09:03:49Z

Paolo Bonzini wrote on 2014-07-17:
> Il 17/07/2014 06:56, Wanpeng Li ha scritto:
>> This patch fix bug reported in
>> https://bugzilla.kernel.org/show_bug.cgi?id=73331, after the patch
>> http://www.spinics.net/lists/kvm/msg105230.html applied, there is some
>> progress and the L2 can boot up, however, slowly. The original idea of
>> this fix vid injection patch is from "Zhang, Yang Z"
>> <yang.z.zhang@intel.com>.
>>
>> Interrupt which delivered by vid should be injected to L1 by L0 if
>> current is in L1, or should be injected to L2 by L0 through the old
>> injection way if L1 doesn't have set VM_EXIT_ACK_INTR_ON_EXIT. The
>> current logic doen't consider these cases. This patch fix it by vid
>> intr to L1 if current is L1 or L2 through old injection way if L1
>> doen't have VM_EXIT_ACK_INTR_ON_EXIT set.
>>
>> Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com>
>> Signed-off-by: "Zhang, Yang Z" <yang.z.zhang@intel.com>
>> ---
>> arch/x86/kvm/vmx.c | 18 ++++++++++++++++--
>> 1 file changed, 16 insertions(+), 2 deletions(-)
>> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index
>> 021d84a..ad36646 100644
>> --- a/arch/x86/kvm/vmx.c
>> +++ b/arch/x86/kvm/vmx.c
>> @@ -7112,8 +7112,22 @@ static void vmx_hwapic_irr_update(struct
>> kvm_vcpu *vcpu, int max_irr) {
>> if (max_irr == -1)
>> return;
>> -
>> - vmx_set_rvi(max_irr);
>> + if (!is_guest_mode(vcpu)) {
>> + vmx_set_rvi(max_irr);
>> + } else if (is_guest_mode(vcpu) && !nested_exit_on_intr(vcpu)) {
>> + /*
>> + * Fall back to old way to inject the interrupt since there
>> + * is no vAPIC-v for L2.
>> + */
>> + if (vcpu->arch.exception.pending ||
>> + vcpu->arch.nmi_injected ||
>> + vcpu->arch.interrupt.pending)
>> + return;
>> + else if (vmx_interrupt_allowed(vcpu)) {
>> + kvm_queue_interrupt(vcpu, max_irr, false);
>> + vmx_inject_irq(vcpu);
>> + }
>> + }
>> }
>>
>> static void vmx_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64
>> *eoi_exit_bitmap)
>>
>
> What hypervisor did you test with? nested_exit_on_intr(vcpu) will

Jailhouse will clear External-interrupt exiting bit. Am I right? Jan.

> return true for both Xen and KVM (nested_exit_on_intr is not the same
> thing as ACK_INTR_ON_EXIT).

I guess he want to say External-interrupt exiting bit not ACK_INTR_ON_EXIT.

>
> Paolo

Best regards,
Yang